1. Field of the Invention
The present invention relates to new dichloroacetamide and trichloroacetamide derivatives, processes for their preparation and their application as antidotes against herbicides.
2. Description of the Prior Art
Herbicides existing at the present time may be classed in two categories: total herbicides, which destroy all plants, and selective herbicides. The latter, which are the most valuable in agriculture, enable the weeds present in croplands to be destroyed without harming the cultivated plant and for this reason are said to be selective for the cultivated plant. Unfortunately, it often occurs that this selectivity may not be perfect at the dose used and that the selective herbicides show some phytotoxicity towards the cultivated plant.
There may also be used, in association with herbicides, products said to be antidotes against herbicides which have the property of imparting to the herbicides an increased selectivity or new selectivities, without being prejudicial to their herbicidal quality. In other words, the antidote makes the phytotoxicity of the herbicide towards the cultivated plant disappear entirely or at least to a great extent without reducing its phytotoxicity towards unwanted plants.
Such antidotes against herbicides have been described, for example in French Pat. No. 2,133,793, corresponding at least in part to U.S. Pat. Nos. 4,137,070, 2,212,336, corresponding at least in part to U.S. Pat. Nos. 3,989,503, 2,215,170, 2,228,065, 2,309,546 corresponding at least in part to U.S. Pat. Nos. 4,072,688 and 2,310,348, and in U.S. Pat. Nos. 3,867,444, 3,923,494, 3,931,313 and 3,959,304.
The object of the present invention is to obtain chemically new compounds which are themselves active as antidotes against herbicides.